Christopher L. Mealy
\nDaniel T. Gottuk
\nHughes Associates, Inc.<\/p>\n
Presented at\u00a0International Symposium on Fire Investigation<\/a>, 2012<\/p>\n ABSTRACT<\/p>\n The prevalence of gypsum wallboard in fire scenes makes it a potentially valuable source of information to fire\u00a0investigators when assessing a fire scene. The exposure of gypsum wallboard to heat from a fire can result in\u00a0calcination, which in turn can theoretically be correlated to the total heat exposure to that area. Therefore, if\u00a0properly characterized, a calcination depth profile of a given enclosure could provide fire investigators with a\u00a0detailed history of the total heat exposure to the walls and ceiling of the space. This history, when combined with\u00a0other findings, could provide valuable insight as to where the area of origin was located or how the fire developed.\u00a0The approach taken in this work incorporated small- and full-scale testing to accomplish several goals: 1) develop an\u00a0objective method for measuring the calcination depth of gypsum wallboard, 2) assess the utility of the calcination\u00a0depth surveys in full-scale fires, and 3) characterize the impact of suppression water on calcination depth\u00a0measurements. In this work a probing pressure of 0.86 kg\/mm2\u00a0 (1175 psi) was identified as providing accurate\u00a0calcination depth measurements. The benefit of calcination depth surveys in full-scale enclosure fire scenarios was\u00a0realized primarily for cases where visual patterns were not obvious. The application of water to calcined GWB was\u00a0found to alter the measured depth of calcination by an average 18 percent, when collected 24 hours after\u00a0heating\/water application and less than five percent after 30 days. This data suggests that if measurements are to be\u00a0collected in areas that have been wetted by suppression activities for any extended period of time, it would be\u00a0advisable to delay measurements until the water has been removed.<\/p>\n Download the complete paper<\/a> here<\/p>\n","protected":false},"excerpt":{"rendered":" Christopher L. Mealy Daniel T. Gottuk Hughes Associates, Inc. Presented at\u00a0International Symposium on Fire Investigation, 2012 ABSTRACT The prevalence of gypsum wallboard in fire scenes makes it a potentially valuable source of information to fire\u00a0investigators when assessing a fire scene. The exposure of gypsum wallboard to heat from a fire can result in\u00a0calcination, which in … Continue reading A Study of Calcination of Gypsum Wallboard<\/span>